So I am thinking it is really an error using the rewrite rule, because the !.php must have been matched up, unless of course I am reading through the log wrong.

----------------edit 2 ------------------
Appears like this might be a couple part error.
Part 1 javascript is loading a 500 error
Part 2 the page is not outputting this content.
I have tossed a couple of echo's in to the page, and also the URL is retrievable. Unsure where that 3738 is originating from.

CRAZY!!!
Still unsure how/why this really is happening on my small test server, and incredibly worried about the way it will progress, however the code now creates push &amplifier test.

I believe the 500 error was very misleading. There wasn't a mistake, however the page wasn't coming back this content it must have.

This is what was happening.

The hyperlink I had been looking to get was format.php?output=queries

Now, with PHP, i ought to need to get the variable $_GET['output'], however i make use of the same page being an include, and so i make use of this

if(!isset($output))

For whatever reason on my small test server output had been set, even if the page has been retrieved inside a new window. How's that possible? It's only within the URL, so how exactly does PHP understand how to assign it?

Anyway, I understand the page that utilizes format.php includes a variable which i avoid using elsewhere, and so i check for your variable now.
Problem fixed.

After I did that, the page loads, and firebug shows nothing.
Now you ask , now, why did Firebug interpret a near empty page like a 500 error?